design a 12 amp TRIPLE THROW light switch box

[jef_a]

HI,
I need to design a control box for lights to be used in a theatre show.
The box will be foot operated, and control three lights (call them A, B , C)
--> Only one light is on at a time.

Ideally the box has FOUR buttons::

Punch button 'A' and light A comes on (light B & C off)
Punch 'B' and light B comes on (light A & C off)
Punch 'C' and light C is on (B & A are off)
Punch 'Off' and all lights are off.

Each light runs on 24v, 250 W, so drawing about 12 amps. I have had trouble finding TRIPLE switches that could do the job. Rotary are no use (impossible for foot operation), mini-toggles and guitar designed foot switches tend to be too small amperage rating.

At the moment I am using a simple system of three DPDT switches in a 'series' that are (barely) foot operable:

-switch 1: turns switch 2 on, or all lights off
-switch 2: turns switch 3 on, or turns light A on
-switch 3: turns light B on (C off) or light C on (B off).

Too much switching though.... argh! I need to be able to just jump from one light to another quickly, and without delay. Any ideas, suggestions to improve? Maybe a relay design? ... simple and reliable is preferred.

Thanks- jeff

 

[KJ6EAD]

You can use 3 3PDT relays but the wiring is a little complex or you can use some logic to drive 3 SPST relays. This circuit could be used as a control by wiring in your own switches and driving your relays from the LED outputs: **broken link removed**.